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Diffstat (limited to 'drivers/serial/serial_ks8695.c')
-rw-r--r--drivers/serial/serial_ks8695.c657
1 files changed, 657 insertions, 0 deletions
diff --git a/drivers/serial/serial_ks8695.c b/drivers/serial/serial_ks8695.c
new file mode 100644
index 000000000000..c5346d677315
--- /dev/null
+++ b/drivers/serial/serial_ks8695.c
@@ -0,0 +1,657 @@
+/*
+ * drivers/serial/serial_ks8695.c
+ *
+ * Driver for KS8695 serial ports
+ *
+ * Based on drivers/serial/serial_amba.c, by Kam Lee.
+ *
+ * Copyright 2002-2005 Micrel Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ */
+#include <linux/module.h>
+#include <linux/tty.h>
+#include <linux/ioport.h>
+#include <linux/init.h>
+#include <linux/serial.h>
+#include <linux/console.h>
+#include <linux/sysrq.h>
+#include <linux/device.h>
+
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/mach/irq.h>
+
+#include <asm/arch/regs-uart.h>
+#include <asm/arch/regs-irq.h>
+
+#if defined(CONFIG_SERIAL_KS8695_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
+#define SUPPORT_SYSRQ
+#endif
+
+#include <linux/serial_core.h>
+
+
+#define SERIAL_KS8695_MAJOR 204
+#define SERIAL_KS8695_MINOR 16
+#define SERIAL_KS8695_DEVNAME "ttyAM"
+
+#define SERIAL_KS8695_NR 1
+
+/*
+ * Access macros for the KS8695 UART
+ */
+#define UART_GET_CHAR(p) (__raw_readl((p)->membase + KS8695_URRB) & 0xFF)
+#define UART_PUT_CHAR(p, c) __raw_writel((c), (p)->membase + KS8695_URTH)
+#define UART_GET_FCR(p) __raw_readl((p)->membase + KS8695_URFC)
+#define UART_PUT_FCR(p, c) __raw_writel((c), (p)->membase + KS8695_URFC)
+#define UART_GET_MSR(p) __raw_readl((p)->membase + KS8695_URMS)
+#define UART_GET_LSR(p) __raw_readl((p)->membase + KS8695_URLS)
+#define UART_GET_LCR(p) __raw_readl((p)->membase + KS8695_URLC)
+#define UART_PUT_LCR(p, c) __raw_writel((c), (p)->membase + KS8695_URLC)
+#define UART_GET_MCR(p) __raw_readl((p)->membase + KS8695_URMC)
+#define UART_PUT_MCR(p, c) __raw_writel((c), (p)->membase + KS8695_URMC)
+#define UART_GET_BRDR(p) __raw_readl((p)->membase + KS8695_URBD)
+#define UART_PUT_BRDR(p, c) __raw_writel((c), (p)->membase + KS8695_URBD)
+
+#define KS8695_CLR_TX_INT() __raw_writel(1 << KS8695_IRQ_UART_TX, KS8695_IRQ_VA + KS8695_INTST)
+
+#define UART_DUMMY_LSR_RX 0x100
+#define UART_PORT_SIZE (KS8695_USR - KS8695_URRB + 4)
+
+#define tx_enabled(port) ((port)->unused[0])
+#define rx_enabled(port) ((port)->unused[1])
+
+
+#ifdef SUPPORT_SYSRQ
+static struct console ks8695_console;
+#endif
+
+static void ks8695uart_stop_tx(struct uart_port *port)
+{
+ if (tx_enabled(port)) {
+ disable_irq(KS8695_IRQ_UART_TX);
+ tx_enabled(port) = 0;
+ }
+}
+
+static void ks8695uart_start_tx(struct uart_port *port)
+{
+ if (!tx_enabled(port)) {
+ enable_irq(KS8695_IRQ_UART_TX);
+ tx_enabled(port) = 1;
+ }
+}
+
+static void ks8695uart_stop_rx(struct uart_port *port)
+{
+ if (rx_enabled(port)) {
+ disable_irq(KS8695_IRQ_UART_RX);
+ rx_enabled(port) = 0;
+ }
+}
+
+static void ks8695uart_enable_ms(struct uart_port *port)
+{
+ enable_irq(KS8695_IRQ_UART_MODEM_STATUS);
+}
+
+static void ks8695uart_disable_ms(struct uart_port *port)
+{
+ disable_irq(KS8695_IRQ_UART_MODEM_STATUS);
+}
+
+static irqreturn_t ks8695uart_rx_chars(int irq, void *dev_id)
+{
+ struct uart_port *port = dev_id;
+ struct tty_struct *tty = port->info->tty;
+ unsigned int status, ch, lsr, flg, max_count = 256;
+
+ status = UART_GET_LSR(port); /* clears pending LSR interrupts */
+ while ((status & URLS_URDR) && max_count--) {
+ ch = UART_GET_CHAR(port);
+ flg = TTY_NORMAL;
+
+ port->icount.rx++;
+
+ /*
+ * Note that the error handling code is
+ * out of the main execution path
+ */
+ lsr = UART_GET_LSR(port) | UART_DUMMY_LSR_RX;
+ if (unlikely(lsr & (URLS_URBI | URLS_URPE | URLS_URFE | URLS_URROE))) {
+ if (lsr & URLS_URBI) {
+ lsr &= ~(URLS_URFE | URLS_URPE);
+ port->icount.brk++;
+ if (uart_handle_break(port))
+ goto ignore_char;
+ }
+ if (lsr & URLS_URPE)
+ port->icount.parity++;
+ if (lsr & URLS_URFE)
+ port->icount.frame++;
+ if (lsr & URLS_URROE)
+ port->icount.overrun++;
+
+ lsr &= port->read_status_mask;
+
+ if (lsr & URLS_URBI)
+ flg = TTY_BREAK;
+ else if (lsr & URLS_URPE)
+ flg = TTY_PARITY;
+ else if (lsr & URLS_URFE)
+ flg = TTY_FRAME;
+ }
+
+ if (uart_handle_sysrq_char(port, ch))
+ goto ignore_char;
+
+ uart_insert_char(port, lsr, URLS_URROE, ch, flg);
+
+ignore_char:
+ status = UART_GET_LSR(port);
+ }
+ tty_flip_buffer_push(tty);
+
+ return IRQ_HANDLED;
+}
+
+
+static irqreturn_t ks8695uart_tx_chars(int irq, void *dev_id)
+{
+ struct uart_port *port = dev_id;
+ struct circ_buf *xmit = &port->info->xmit;
+ unsigned int count;
+
+ if (port->x_char) {
+ KS8695_CLR_TX_INT();
+ UART_PUT_CHAR(port, port->x_char);
+ port->icount.tx++;
+ port->x_char = 0;
+ return IRQ_HANDLED;
+ }
+
+ if (uart_tx_stopped(port) || uart_circ_empty(xmit)) {
+ ks8695uart_stop_tx(port);
+ return IRQ_HANDLED;
+ }
+
+ count = 16; /* fifo size */
+ while (!uart_circ_empty(xmit) && (count-- > 0)) {
+ KS8695_CLR_TX_INT();
+ UART_PUT_CHAR(port, xmit->buf[xmit->tail]);
+
+ xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+ port->icount.tx++;
+ }
+
+ if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+ uart_write_wakeup(port);
+
+ if (uart_circ_empty(xmit))
+ ks8695uart_stop_tx(port);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t ks8695uart_modem_status(int irq, void *dev_id)
+{
+ struct uart_port *port = dev_id;
+ unsigned int status;
+
+ /*
+ * clear modem interrupt by reading MSR
+ */
+ status = UART_GET_MSR(port);
+
+ if (status & URMS_URDDCD)
+ uart_handle_dcd_change(port, status & URMS_URDDCD);
+
+ if (status & URMS_URDDST)
+ port->icount.dsr++;
+
+ if (status & URMS_URDCTS)
+ uart_handle_cts_change(port, status & URMS_URDCTS);
+
+ if (status & URMS_URTERI)
+ port->icount.rng++;
+
+ wake_up_interruptible(&port->info->delta_msr_wait);
+
+ return IRQ_HANDLED;
+}
+
+static unsigned int ks8695uart_tx_empty(struct uart_port *port)
+{
+ return (UART_GET_LSR(port) & URLS_URTE) ? TIOCSER_TEMT : 0;
+}
+
+static unsigned int ks8695uart_get_mctrl(struct uart_port *port)
+{
+ unsigned int result = 0;
+ unsigned int status;
+
+ status = UART_GET_MSR(port);
+ if (status & URMS_URDCD)
+ result |= TIOCM_CAR;
+ if (status & URMS_URDSR)
+ result |= TIOCM_DSR;
+ if (status & URMS_URCTS)
+ result |= TIOCM_CTS;
+ if (status & URMS_URRI)
+ result |= TIOCM_RI;
+
+ return result;
+}
+
+static void ks8695uart_set_mctrl(struct uart_port *port, u_int mctrl)
+{
+ unsigned int mcr;
+
+ mcr = UART_GET_MCR(port);
+ if (mctrl & TIOCM_RTS)
+ mcr |= URMC_URRTS;
+ else
+ mcr &= ~URMC_URRTS;
+
+ if (mctrl & TIOCM_DTR)
+ mcr |= URMC_URDTR;
+ else
+ mcr &= ~URMC_URDTR;
+
+ UART_PUT_MCR(port, mcr);
+}
+
+static void ks8695uart_break_ctl(struct uart_port *port, int break_state)
+{
+ unsigned int lcr;
+
+ lcr = UART_GET_LCR(port);
+
+ if (break_state == -1)
+ lcr |= URLC_URSBC;
+ else
+ lcr &= ~URLC_URSBC;
+
+ UART_PUT_LCR(port, lcr);
+}
+
+static int ks8695uart_startup(struct uart_port *port)
+{
+ int retval;
+
+ set_irq_flags(KS8695_IRQ_UART_TX, IRQF_VALID | IRQF_NOAUTOEN);
+ tx_enabled(port) = 0;
+ rx_enabled(port) = 1;
+
+ /*
+ * Allocate the IRQ
+ */
+ retval = request_irq(KS8695_IRQ_UART_TX, ks8695uart_tx_chars, IRQF_DISABLED, "UART TX", port);
+ if (retval)
+ goto err_tx;
+
+ retval = request_irq(KS8695_IRQ_UART_RX, ks8695uart_rx_chars, IRQF_DISABLED, "UART RX", port);
+ if (retval)
+ goto err_rx;
+
+ retval = request_irq(KS8695_IRQ_UART_LINE_STATUS, ks8695uart_rx_chars, IRQF_DISABLED, "UART LineStatus", port);
+ if (retval)
+ return err_ls;
+
+ retval = request_irq(KS8695_IRQ_UART_MODEM_STATUS, ks8695uart_modem_status, IRQF_DISABLED, "UART ModemStatus", port);
+ if (retval)
+ return err_ms;
+
+ return 0;
+
+err_ms:
+ free_irq(KS8695_IRQ_UART_LINE_STATUS, port);
+err_ls:
+ free_irq(KS8695_IRQ_UART_RX, port);
+err_rx:
+ free_irq(KS8695_IRQ_UART_TX, port);
+err_tx:
+ return retval;
+}
+
+static void ks8695uart_shutdown(struct uart_port *port)
+{
+ /*
+ * Free the interrupt
+ */
+ free_irq(KS8695_IRQ_UART_RX, port);
+ free_irq(KS8695_IRQ_UART_TX, port);
+ free_irq(KS8695_IRQ_UART_MODEM_STATUS, port);
+ free_irq(KS8695_IRQ_UART_LINE_STATUS, port);
+
+ /* disable break condition and fifos */
+ UART_PUT_LCR(port, UART_GET_LCR(port) & ~URLC_URSBC);
+ UART_PUT_FCR(port, UART_GET_FCR(port) & ~URFC_URFE);
+}
+
+static void ks8695uart_set_termios(struct uart_port *port, struct ktermios *termios, struct ktermios *old)
+{
+ unsigned int lcr, fcr = 0;
+ unsigned long flags;
+ unsigned int baud, quot;
+
+ /*
+ * Ask the core to calculate the divisor for us.
+ */
+ baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
+ quot = uart_get_divisor(port, baud);
+
+ switch (termios->c_cflag & CSIZE) {
+ case CS5:
+ lcr = URCL_5;
+ break;
+ case CS6:
+ lcr = URCL_6;
+ break;
+ case CS7:
+ lcr = URCL_7;
+ break;
+ default:
+ lcr = URCL_8;
+ break;
+ }
+
+ /* stop bits */
+ if (termios->c_cflag & CSTOPB)
+ lcr |= URLC_URSB;
+
+ /* parity */
+ if (termios->c_cflag & PARENB) {
+ if (termios->c_cflag & CMSPAR) { /* Mark or Space parity */
+ if (termios->c_cflag & PARODD)
+ lcr |= URPE_MARK;
+ else
+ lcr |= URPE_SPACE;
+ }
+ else if (termios->c_cflag & PARODD)
+ lcr |= URPE_ODD;
+ else
+ lcr |= URPE_EVEN;
+ }
+
+ if (port->fifosize > 1)
+ fcr = URFC_URFRT_8 | URFC_URTFR | URFC_URRFR | URFC_URFE;
+
+ spin_lock_irqsave(&port->lock, flags);
+
+ /*
+ * Update the per-port timeout.
+ */
+ uart_update_timeout(port, termios->c_cflag, baud);
+
+ port->read_status_mask = URLS_URROE;
+ if (termios->c_iflag & INPCK)
+ port->read_status_mask |= (URLS_URFE | URLS_URPE);
+ if (termios->c_iflag & (BRKINT | PARMRK))
+ port->read_status_mask |= URLS_URBI;
+
+ /*
+ * Characters to ignore
+ */
+ port->ignore_status_mask = 0;
+ if (termios->c_iflag & IGNPAR)
+ port->ignore_status_mask |= (URLS_URFE | URLS_URPE);
+ if (termios->c_iflag & IGNBRK) {
+ port->ignore_status_mask |= URLS_URBI;
+ /*
+ * If we're ignoring parity and break indicators,
+ * ignore overruns too (for real raw support).
+ */
+ if (termios->c_iflag & IGNPAR)
+ port->ignore_status_mask |= URLS_URROE;
+ }
+
+ /*
+ * Ignore all characters if CREAD is not set.
+ */
+ if ((termios->c_cflag & CREAD) == 0)
+ port->ignore_status_mask |= UART_DUMMY_LSR_RX;
+
+ /* first, disable everything */
+ if (UART_ENABLE_MS(port, termios->c_cflag))
+ ks8695uart_enable_ms(port);
+ else
+ ks8695uart_disable_ms(port);
+
+ /* Set baud rate */
+ UART_PUT_BRDR(port, quot);
+
+ UART_PUT_LCR(port, lcr);
+ UART_PUT_FCR(port, fcr);
+
+ spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static const char *ks8695uart_type(struct uart_port *port)
+{
+ return port->type == PORT_KS8695 ? "KS8695" : NULL;
+}
+
+/*
+ * Release the memory region(s) being used by 'port'
+ */
+static void ks8695uart_release_port(struct uart_port *port)
+{
+ release_mem_region(port->mapbase, UART_PORT_SIZE);
+}
+
+/*
+ * Request the memory region(s) being used by 'port'
+ */
+static int ks8695uart_request_port(struct uart_port *port)
+{
+ return request_mem_region(port->mapbase, UART_PORT_SIZE,
+ "serial_ks8695") != NULL ? 0 : -EBUSY;
+}
+
+/*
+ * Configure/autoconfigure the port.
+ */
+static void ks8695uart_config_port(struct uart_port *port, int flags)
+{
+ if (flags & UART_CONFIG_TYPE) {
+ port->type = PORT_KS8695;
+ ks8695uart_request_port(port);
+ }
+}
+
+/*
+ * verify the new serial_struct (for TIOCSSERIAL).
+ */
+static int ks8695uart_verify_port(struct uart_port *port, struct serial_struct *ser)
+{
+ int ret = 0;
+
+ if (ser->type != PORT_UNKNOWN && ser->type != PORT_KS8695)
+ ret = -EINVAL;
+ if (ser->irq != port->irq)
+ ret = -EINVAL;
+ if (ser->baud_base < 9600)
+ ret = -EINVAL;
+ return ret;
+}
+
+static struct uart_ops ks8695uart_pops = {
+ .tx_empty = ks8695uart_tx_empty,
+ .set_mctrl = ks8695uart_set_mctrl,
+ .get_mctrl = ks8695uart_get_mctrl,
+ .stop_tx = ks8695uart_stop_tx,
+ .start_tx = ks8695uart_start_tx,
+ .stop_rx = ks8695uart_stop_rx,
+ .enable_ms = ks8695uart_enable_ms,
+ .break_ctl = ks8695uart_break_ctl,
+ .startup = ks8695uart_startup,
+ .shutdown = ks8695uart_shutdown,
+ .set_termios = ks8695uart_set_termios,
+ .type = ks8695uart_type,
+ .release_port = ks8695uart_release_port,
+ .request_port = ks8695uart_request_port,
+ .config_port = ks8695uart_config_port,
+ .verify_port = ks8695uart_verify_port,
+};
+
+static struct uart_port ks8695uart_ports[SERIAL_KS8695_NR] = {
+ {
+ .membase = (void *) KS8695_UART_VA,
+ .mapbase = KS8695_UART_VA,
+ .iotype = SERIAL_IO_MEM,
+ .irq = KS8695_IRQ_UART_TX,
+ .uartclk = CLOCK_TICK_RATE * 16,
+ .fifosize = 16,
+ .ops = &ks8695uart_pops,
+ .flags = ASYNC_BOOT_AUTOCONF,
+ .line = 0,
+ }
+};
+
+#ifdef CONFIG_SERIAL_KS8695_CONSOLE
+static void ks8695_console_putchar(struct uart_port *port, int ch)
+{
+ while (!(UART_GET_LSR(port) & URLS_URTHRE))
+ barrier();
+
+ UART_PUT_CHAR(port, ch);
+}
+
+static void ks8695_console_write(struct console *co, const char *s, u_int count)
+{
+ struct uart_port *port = ks8695uart_ports + co->index;
+
+ uart_console_write(port, s, count, ks8695_console_putchar);
+}
+
+static void __init ks8695_console_get_options(struct uart_port *port, int *baud, int *parity, int *bits)
+{
+ unsigned int lcr;
+
+ lcr = UART_GET_LCR(port);
+
+ switch (lcr & URLC_PARITY) {
+ case URPE_ODD:
+ *parity = 'o';
+ break;
+ case URPE_EVEN:
+ *parity = 'e';
+ break;
+ default:
+ *parity = 'n';
+ }
+
+ switch (lcr & URLC_URCL) {
+ case URCL_5:
+ *bits = 5;
+ break;
+ case URCL_6:
+ *bits = 6;
+ break;
+ case URCL_7:
+ *bits = 7;
+ break;
+ default:
+ *bits = 8;
+ }
+
+ *baud = port->uartclk / (UART_GET_BRDR(port) & 0x0FFF);
+ *baud /= 16;
+ *baud &= 0xFFFFFFF0;
+}
+
+static int __init ks8695_console_setup(struct console *co, char *options)
+{
+ struct uart_port *port;
+ int baud = 115200;
+ int bits = 8;
+ int parity = 'n';
+ int flow = 'n';
+
+ /*
+ * Check whether an invalid uart number has been specified, and
+ * if so, search for the first available port that does have
+ * console support.
+ */
+ port = uart_get_console(ks8695uart_ports, SERIAL_KS8695_NR, co);
+
+ if (options)
+ uart_parse_options(options, &baud, &parity, &bits, &flow);
+ else
+ ks8695_console_get_options(port, &baud, &parity, &bits);
+
+ return uart_set_options(port, co, baud, parity, bits, flow);
+}
+
+extern struct uart_driver ks8695_reg;
+
+static struct console ks8695_console = {
+ .name = SERIAL_KS8695_DEVNAME,
+ .write = ks8695_console_write,
+ .device = uart_console_device,
+ .setup = ks8695_console_setup,
+ .flags = CON_PRINTBUFFER,
+ .index = -1,
+ .data = &ks8695_reg,
+};
+
+static int __init ks8695_console_init(void)
+{
+ register_console(&ks8695_console);
+ return 0;
+}
+
+console_initcall(ks8695_console_init);
+
+#define KS8695_CONSOLE &ks8695_console
+#else
+#define KS8695_CONSOLE NULL
+#endif
+
+static struct uart_driver ks8695_reg = {
+ .owner = THIS_MODULE,
+ .driver_name = "serial_ks8695",
+ .dev_name = SERIAL_KS8695_DEVNAME,
+ .major = SERIAL_KS8695_MAJOR,
+ .minor = SERIAL_KS8695_MINOR,
+ .nr = SERIAL_KS8695_NR,
+ .cons = KS8695_CONSOLE,
+};
+
+static int __init ks8695uart_init(void)
+{
+ int i, ret;
+
+ printk(KERN_INFO "Serial: Micrel KS8695 UART driver\n");
+
+ ret = uart_register_driver(&ks8695_reg);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < SERIAL_KS8695_NR; i++)
+ uart_add_one_port(&ks8695_reg, &ks8695uart_ports[0]);
+
+ return 0;
+}
+
+static void __exit ks8695uart_exit(void)
+{
+ int i;
+
+ for (i = 0; i < SERIAL_KS8695_NR; i++)
+ uart_remove_one_port(&ks8695_reg, &ks8695uart_ports[0]);
+ uart_unregister_driver(&ks8695_reg);
+}
+
+module_init(ks8695uart_init);
+module_exit(ks8695uart_exit);
+
+MODULE_DESCRIPTION("KS8695 serial port driver");
+MODULE_AUTHOR("Micrel Inc.");
+MODULE_LICENSE("GPL");
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